The Perfect Putt with SOLIDWORKS Motion

By Paolo Olmos

For all of you golfers out there, the Masters tournament has just begun, and it’s a great opportunity to watch the best players in the world compete. One thing that always amazes me when I watch the tournament is how they can make long putts on some of the toughest greens. I recently read this article that said if your putter is aimed 1 degree to the left or right of the hole for a flat 10 foot putt, you will miss. Talking to my instructor about this small margin for error in putter alignment, he said that you can compensate for a 1 degree misalignment to the left of the hole for a 10 foot putt, by swinging along a plane 1 degree to the right of the hole.

So in theory, any misalignment in the putter face can be compensated for by the path of your swing and vice versa. When trying to test things myself, I realized that there are so many factors to consider such as the bumps of the green, the consistency of my putting stroke, and even the consistency of the golf ball. All of these factors make it difficult to know what really caused a missed putt. So I turned to SOLIDWORKS Motion which allowed me to account for the kinematics and create a consistent setup in order to compare results between 3 scenarios:

• The face of the putter and swing path aligned with the target
• The face of the putter pointed left of the target 1 degree and a swing path aligned with the target
• The face of the putter pointed left of the target 1 degree and a swing path 1 degree right of the target

So here is how I setup these analyses:

Created An Assembly

10 foot Putt Assembly

Defined The Path Of The Stroke And Mates

I used a circular sketch that went through the center of the putter face and the contact point on the golf ball. I defined a path mate between the center point of the putter face and sketch. I also created a mate that kept the putter parallel to the putting surface.

Path of the putting stroke

The sketch was created on a reference plane which represented the swing path and allowed for the angle to be changed. Finally a mate was created to change the angle of the putter face.  

Swing Path And Putter Face Angle

Defined Contact

In SOLIDWORKS Motion I created a contact feature to define the elastic properties when the putter hits the golf ball. In this case, I defined the coefficient of restitution which sets the ratio of relative velocities of the putter and ball before and after impact.

Elastic Properties Between the Putter and Golf Ball

Restitution coefficient obtained from: Adli Haron, K A Ismail (2012). Coefficient of restitution of sports balls: A normal drop test. Retrieved from iopscience.iop.org/1757-899X/36/1/012038/pdf/1757-899X_36_1_012038.pdf Using another contact feature, I defined the friction properties between the golf ball and grass in order to simulate the proper roll of the golf ball towards the hole.

Friction Properties Between the Golf Ball and Grass

Friction properties obtained from: Scott K. Perry (2002). The Proof Is in the Putting. Retrieved from http://home.comcast.net/~saintjohnboscooffice/images/martikean/articles/38.pdf

Defined Gravity

Finally I needed to define the direction of gravity in order to have the ball stay rolling on the ground. Gravity is also what will drive the putting stroke when the putter is started a set distance away from the ball along the arc of the stroke.

Definition of Gravity

So what were my results?

Well as it turns out, for a flat 10 foot putt and aiming just 1 degree to the left of the hole with a stroke made along a straight path to the hole, it is true that you will just barely miss the hole. Now if you compensate for the 1 degree face angle left of the target with a stroke that goes along a path 1 degree right of the hole, you will make your putt. Below is a summary of the results I obtained along with links to videos for a few of the results.